At least two to six months before school starts, get hold of audio/video lectures on the following standard fist year subjects: Torts; Contracts; Civil Procedure (by A. Miller); and Criminal Law. These are easy to find on E*Bay, lawbooks.com and elsewhere. They are lectures which summarize each first year topic. Also review study guides which explain and outline each of these topics such as Emanuel Law Outlines or Gilbert Study Guides. Do not use "bar prep" lectures because they assume some subject matter knowledge. If you live near a law school you may wish to compare first year study guides to see which ones best suit your learning style.
Listen to the lectures on Torts or Contracts first (if possible). These are the easiest subjects. The information should START to sink in after five or six times through. If not, consider not going to law school. Listen to the audio cassets everywhere possible: in the car; while walking; at the gym; or at work if your work is physical (and not mental). Try to repeat back a vary bare bones outline of what is on each tape.
Get practice exam questions and/or flash cards for each subject. Practice answering simple questions first. Then move on to longer format essays using an exam taking system as described in Step 4 below. Consider getting hold of, and reviewing, class notes and practice exams for prior years from a student who has recently attended the school that you plan to attend.
Purchase a lecture series and/or books which explain how to take law school exams. Try writing out a few essay exam questions based on fact patterns using the system. It is important to master a system so that you feel confident. Once you are confident, you can then make adjustments to meet the situation presented.
Repeat this process for as many of the first year subjects as possible. Tackle the subjects in this order: Torts, Contracts, Civil Procedure, and Criminal Law. Torts and Contracts are relatively easy. Civil procedure is considered by most to be the most difficult. It will be easier to learn after you have had a bit of experience with another subject. Criminal Law varies greatly with the professor so the benefit of studying in advance may not be as great as with the other subjects.